That was it Thanks :)
John Hunter-4 wrote: > > On Tue, Mar 2, 2010 at 5:13 AM, Dunx <d...@hotmail.co.uk> wrote: >> >> Hi, >> >> I know about the difference between pylab.psd and mlab.psd, but in theory >> the only difference between the returned values is: >> >> pylab.psd = 10*log10(mlab.psd) >> >> Except this is not true, there is noticeable difference: >> >> pylab.psd = 23.4962 (all these pylab.psd values are read from graph) >> 10*log10(mlab.psd) = 17.2852 >> >> pylab.psd = 18.8973 >> 10*log10(mlab.psd) = 12.8149 >> >> pylab.psd = 4.92 >> 10*log10(mlab.psd) = -2.247 >> >> These all look suspiciously out by around 2pi, although by no means >> exact. >> Any ideas? >> >> code is: >> pylab.psd(input, NFFT=512, Fs=sampleRate, window=blackman(512)) #graph >> x,y = mlab.psd(input, NFFT=512, Fs=sampleRate, window=blackman(512)) >> #look >> at x > > What version of mpl are you using? Could you try setting your > matplotlib rc parameter path.simplify to False? There is a known bug > in the released version of mpl that causes path simplification to > render lines improperly. Looking at the code, Axes.psd just calls > mlab.psd and then plots 10*log10(pxx), so if there is a difference the > most likely culprit is a rendering bug. > See http://matplotlib.sourceforge.net/users/customizing.html for > information on how to change your default matplotlib rc parameters. > > Christoph, this is a serious bug that merits a branch bugfix release > ASAP. I will do the src release if you can do the win32 release. > Perhaps we can find someone who can build the OSX binaries for us > since my OSX box is dead. By I don't want to hold the release for > want of OSX binaries since this is a recurrent and serious problem. > > JDH > > ------------------------------------------------------------------------------ > Download Intel® Parallel Studio Eval > Try the new software tools for yourself. Speed compiling, find bugs > proactively, and fine-tune applications for parallel performance. > See why Intel Parallel Studio got high marks during beta. > http://p.sf.net/sfu/intel-sw-dev > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > -- View this message in context: http://old.nabble.com/PSD-amplitude-disparity-tp27754632p27766635.html Sent from the matplotlib - users mailing list archive at Nabble.com. ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
